Vol. 12, Special Issue 7 (2023)

Author(s):
S Ganapathi, GN Dhanapal, Ajmal KK, S Kamala Bai, MN Thimmegowda R, Muthu Raju and BG Vasanthi

Abstract:
A field experiment was conducted at AICRP on Weed Management, MRS, Hebbal, Bengaluru during Kharif 2019 and 2020 to examine the effects of various conservation tillage and weed management approaches on crop nutrient uptake, weeds in kharif maize, and their effects on Kernal production, the available nutrient status of soil after kharif maize harvest, and B:C ratio. The experiment was laid out in a split-plot design with five main plots of different tillage treatments and three sub-plots of different weed management practices replicated thrice. The main plot tillage treatments consisted of conventional tillage, zero tillage, minimum tillage, minimum tillage + zero tillage (combination), and permanent bed. The intensity of tillage and various weed management practices had a significant effect on maize crop nutrient uptake at harvest. In compared to zero tillage (117.9, 28.1, and 91.1 kg N, P₂O₅ and K₂O ha^-1, respectively), permanent raised beds have significantly higher nitrogen, phosphorus, and potassium uptake (142.0, 34.8, and 105.4 kg N, P₂O₅ and K₂O ha^-1, respectively). The maize crop nutrient uptake at harvest was significantly affected by weed management practices. Integrated weed management (138.9, 33.74, and 108.8 kg N, P₂O₅ and K₂O ha^-1, respectively) had significantly higher nitrogen, phosphorus, and potassium uptake than unweeded (control) (97.8, 22.95, and 70.9 kg N, P₂O₅ and K₂O ha^-1, respectively).